The Heartbeat of the Blue Whale

The blue whale, the largest animal ever to have lived on our planet, has a heart that weighs approximately 400 pounds (180 kg) - about the size of a small piano.

But here's where it gets even more fascinating: the heart of a blue whale beats at an incredibly slow pace for an animal of its size.

It beats only 5-6 times per minute while at the surface, and can slow down to just 2 beats per minute during a dive.

To put this into perspective, a human heart beats 60-100 times per minute.

Furthermore, packed with nine litres of blood with every beat, its aorta (the main artery from the heart) is so large that a human could swim through it.

Despite the slow rate, the power of each beat is monumental, easily felt by divers and underwater vehicles.

This slow heartbeat conserves energy and oxygen, allowing the whale to cruise the ocean depths..